Killer Algae
The Bay is being overrun by algae. Billions and billions of the tiny creatures are making life harder on the rest of the ecosystem. The three most common algae in the Bay have been blooming more frequently over the last 20 years, according to researchers at University of Maryland Center for Environmental Science.
Mahogany tide, formally known as Prorocentrum minimum, doubled its average number of annual blooms between 1991 and 2008.
The red algae Karlodinium veneficum, a fish killer when its toxins reach high concentrations, went from less than five annual blooms to more than 30 between 2003 and 2008.
Blue-green algae, the third advancing species in the Bay, reaches beyond Bay creatures to humans. Cyanobacteria straddles the line between algae and bacteria. It’s a bacteria that gets energy from photosynthesis, like algae. And it’s dangerous. This algae releases chemicals poisonous to people, including neurotoxins.
Algae is a natural part of the Bay’s ecosystem, but not in such excess. Large algae blooms block the sunlight that other plants in the Bay need, and this causes a lot of those plants to die. Not long after, the algae dies as well. Then microbes step in to decompose all of the dead plant matter. The microbes deplete oxygen in the water, suffocating other creatures. These algae blooms can strip an area of all life, creating underwater dead zones.
Big algae blooms are caused by nitrogen runoff from farmland, lawns and stormwater. Nitrogen helps algae to grow. Harmful algae blooms are happening all over the world, threatening to destroy whole ecosystems — and change our way of life.